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    1 {-# LANGUAGE DeriveGeneric     #-}
    2 {-# LANGUAGE OverloadedStrings #-}
    3 module Distribution.Client.ProjectFlags (
    4     ProjectFlags(..),
    5     defaultProjectFlags,
    6     projectFlagsOptions,
    7 ) where
    8 
    9 import Distribution.Client.Compat.Prelude
   10 import Prelude ()
   11 
   12 import Distribution.ReadE          (succeedReadE)
   13 import Distribution.Simple.Command (MkOptDescr, OptionField, ShowOrParseArgs (..), boolOpt', option, reqArg)
   14 import Distribution.Simple.Setup   (Flag (..), flagToList, flagToMaybe, toFlag, trueArg)
   15 
   16 data ProjectFlags = ProjectFlags
   17     { flagProjectFileName :: Flag FilePath
   18       -- ^ The cabal project file name; defaults to @cabal.project@.
   19       -- The name itself denotes the cabal project file name, but it also
   20       -- is the base of auxiliary project files, such as
   21       -- @cabal.project.local@ and @cabal.project.freeze@ which are also
   22       -- read and written out in some cases.  If the path is not found
   23       -- in the current working directory, we will successively probe
   24       -- relative to parent directories until this name is found.
   25 
   26     , flagIgnoreProject   :: Flag Bool
   27       -- ^ Whether to ignore the local project (i.e. don't search for cabal.project)
   28       -- The exact interpretation might be slightly different per command.
   29     }
   30   deriving (Show, Generic)
   31 
   32 defaultProjectFlags :: ProjectFlags
   33 defaultProjectFlags = ProjectFlags
   34     { flagProjectFileName = mempty
   35     , flagIgnoreProject   = toFlag False
   36       -- Should we use 'Last' here?
   37     }
   38 
   39 projectFlagsOptions :: ShowOrParseArgs -> [OptionField ProjectFlags]
   40 projectFlagsOptions showOrParseArgs =
   41     [ option [] ["project-file"]
   42         "Set the name of the cabal.project file to search for in parent directories"
   43         flagProjectFileName (\pf flags -> flags { flagProjectFileName = pf })
   44         (reqArg "FILE" (succeedReadE Flag) flagToList)
   45     , option ['z'] ["ignore-project"]
   46         "Ignore local project configuration"
   47         flagIgnoreProject (\v flags -> flags { flagIgnoreProject = v })
   48         (yesNoOpt showOrParseArgs)
   49     ]
   50 
   51 instance Monoid ProjectFlags where
   52     mempty = gmempty
   53     mappend = (<>)
   54 
   55 instance Semigroup ProjectFlags where
   56     (<>) = gmappend
   57 
   58 yesNoOpt :: ShowOrParseArgs -> MkOptDescr (b -> Flag Bool) (Flag Bool -> b -> b) b
   59 yesNoOpt ShowArgs sf lf = trueArg sf lf
   60 yesNoOpt _        sf lf = boolOpt' flagToMaybe Flag (sf, lf) ([], map ("no-" ++) lf) sf lf